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Posts Tagged: SIP Services

As if emergency responders weren’t already overloaded: Increasingly, extortionists are launching debilitating attacks designed to overwhelm the telephone networks of emergency communications centers and personnel, according to a confidential alert jointly issued by the Department of Homeland Security and the FBI.

“TDos” warning

The alert, a copy of which was obtained by KrebsOnSecurity, warns public safety answering points (PSAPs) and emergency communications centers and personnel about a recent spike in so-called “telephony denial-of-service” (TDoS) attacks:

“Information received from multiple jurisdictions indicates the possibility of attacks targeting the telephone systems of public sector entities. Dozens of such attacks have targeted the administrative PSAP lines (not the 911 emergency line). The perpetrators of the attack have launched high volume of calls against the target network, tying up the system from receiving legitimate calls. This type of attack is referred to as a TDoS or Telephony Denial of Service attack. These attacks are ongoing. Many similar attacks have occurred targeting various businesses and public entities, including the financial sector and other public emergency operations interests, including air ambulance, ambulance and hospital communications.”

According to the alert, these recent TDoS attacks are part of a bizarre extortion scheme that apparently starts with a phone call to an organization from an individual claiming to represent a collections company for payday loans. The caller usually has a strong accent of some sort and asks to speak with a current or former employee concerning an outstanding debt. Failing to get payment from an individual or organization, the perpetrator launches a TDoS attack. The organization will be inundated with a continuous stream of calls for an unspecified, but lengthy period of time.